SOLUTION: -3x-4y=27 5x-6y=-7

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Question 546936: -3x-4y=27
5x-6y=-7
Answer by Maths68(1474) About Me  (Show Source):
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-3x-4y=27..............(1)
5x-6y=-7...............(2)
Multiply (1) by 5 and (2) by 3 and add both equations
-15x-20y=135
15x-18y=-21
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-38y=114
-38y%2F-38=114%2F-38
y=-3
Put the value of y in (1)
-3x-4%28-3%29=27
-3x%2B12=27
-3x=27-12
-3x=15
-3x%2F-3=15%2F-3
x=-5
(x,y)=(-5,-3)

Check
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Put the value of x and y in (1)
-3x-4y=27..............(1)
-3%28-5%29-4%28-3%29=27
15%2B12=27
27=27
Put the value of x and y in (2)
5%28-5%29-6%28-3%29=-7
-25%2B18=-7
-7=-7